The disclosed embodiments relate to a communication system in a passenger aircraft, and in particular to a fault-tolerant transmission system for transmitting data from at least one data source to several terminals in the aircraft, according to the preamble part of claim 1.
Until now, in the case of in-flight entertainment (IFE) systems on board large aircraft the central electronics for providing passengers with entertainment programs etc. have been housed in one location. Such central electronics comprise at least one computer, modulators, digital media for storing, and various play units such as audio devices, DVD players etc. as well as a power supply and interface devices. The individual entertainment systems on the seats of the passengers are centrally controlled by the cabin crew by way of a control panel.
The individual seats in the aircraft comprise playback devices for the data from the central electronics, for example audio systems and displays, so that during the flight, each passenger can select from a large range of entertainment programs. These seat units are supplied by way of an on-board network. The on-board network is fed from the central electronics and comprises several distributors that if need be are associated with individual aircraft sub-units. Thus in an aircraft comprising several levels, one distributor for each deck can be provided. On one level of the aircraft, in the case of several seat rows arranged one behind the other, all the seats immediately one behind the other are supplied by a distributor.
In this distributor structure a first terminal is supplied by the distributor, and starting from the first terminal a second terminal is supplied; starting from the second terminal a third terminal is supplied etc.; so that a daisy chain of terminals results which are all supplied with data from the central entertainment system in the aircraft. However, if the connection between two terminals in this chain is interrupted, then inevitably the terminals arranged downstream are also cut off from the supply.